Create look_and_say_sequence.py

[jovbcorreia]

Describe your change:

Add Look-and-Say sequence algorithm to maths directory.

The Look-and-Say sequence generates each term by reading the digits
of the previous term aloud (e.g., 1 -> 11 -> 21 -> 1211 -> 111221).

• Add an algorithm?
• Fix a bug or typo in an existing algorithm?
• Add or change doctests? -- Note: Please avoid changing both code and tests in a single pull request.
• Documentation change?

Checklist:

• I have read CONTRIBUTING.md.
• This pull request is all my own work -- I have not plagiarized.
• I know that pull requests will not be merged if they fail the automated tests.
• This PR only changes one algorithm file. To ease review, please open separate PRs for separate algorithms.
• All new Python files are placed inside an existing directory.
• All filenames are in all lowercase characters with no spaces or dashes.
• All functions and variable names follow Python naming conventions.
• All function parameters and return values are annotated with Python type hints.
• All functions have doctests that pass the automated testing.
• All new algorithms include at least one URL that points to Wikipedia or another similar explanation.
• If this pull request resolves one or more open issues then the description above includes the issue number(s) with a closing keyword: "Fixes #ISSUE-NUMBER".

[algorithms-keeper]

Click here to look at the relevant links ⬇️

🔗 Relevant Links

Repository:

• Contributing guidelines
• Project Euler solution guidelines

Python:

• Formatted string literals (f-strings)
• Type hints
• doctest
• unittest
• pytest

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[algorithms-keeper]

Please provide return type hint for the function: look_and_say_sequence. If the function does not return a value, please provide the type hint as: def function() -> None:

[Jags-08]

The recursive bounding here is an elegant solution to avoiding heap exhaustion on larger inputs. Nice work!

[Jags-08]

Just following up—if you need any help mapping these bound validations into a PyTest workflow, let me know. I can spin up a quick GH Action matrix for it.

[Jags-08]

Actually, looking closer at the heap traces, the generator expression in line 42 might be slightly more memory efficient than the list comprehension, but it's arguably negligible for this data set. Great PR.